Photogrammetric apparatus



July 4, 1933.

U. NISTRI PHOTOGRAMMETRI C APPARATUS Filed Jul 19, 1930 6 Sheets-Sheet lJuly 4, 1933. u. NISTRI 1,916,487

PHOTOGRAMMETR I C APPARATUS Filed July 19, 1950 6 Sheets-Sheet 2PHOTOGRAMMETRIC APPARATUS July 4, 1933. u. NISTRI PHOTOGRAMMETRICAPPARATUS 6' Sheets-Sheet 4 Filed July 19. 1930 July 4, 1933. u. NISTRI1,916,487

PHOTOGRAMME TR I C APPARATUS Filed July 19, 1950 e Sheets-Sheet' s July4, 1933. u. NISTRI 1,916,487

PHOTOGRAMMETRIC APPIARATIUS Filed July 19, 1930 6 Sheets-Sheet 6Patented July 7 4, 1 933 UNI T'EDJST ATEs. PATENT"oF FICE i .uivmnnro'nrsrnr, orno ME, ITALY rHoroGRA nETRIc ArrAnA'rUs Application filedJuly 19,1930, s rial No; 469,117, and in Italy .nn 27, 1929.

The present invention has reference to-an apparatus. by means of whichby using'two photographs of a certain tract-of land, ob-

, tained from two points of'known position, land with photographiccameras of which the focal distance is known, and which 'are'disposedwith known azimuthal and zenithal directions, allows, by means offindingthe Y coincidence of'the points of the projections f of the saidphotographs upon movable screens, to obtain in an easy and rapid man herthe coordinates of isolated pointsor to draw lines of equal level, inorder to obtain the representation of the land.

1 The principle on which the said photo-' grammetric apparatus isbasedis already known in photogrammetric practice and can be brieflydescribed as follows:

V (a) The two photographs of the same object (i. e. a land tract)obtainedwith the axes disposed in any position, from land or from aboardan aircraft, are. inserted into two optical systems of projection, withthe constants of internal'orientation (principal distance and principalpoint) arrangediin a position identical to that whichthey hadf inrespect to the optical'system that was used for obtaining the image atthe moment ofex- O posure. g

(b) The three or four points of the land tract having known co-ordinatedand which constitutethe basis of the survey, are marked in the space intheir real planimetric and altimetric positions so as to represents themin any chosen scale in their real respective positions. c c c i (c) Thetwo projecting apparatuses with the-two photographic negatives aredirected in respect to these pointsfso as to cause each of them to takeup the position corresponding to that which the optical system used forI taking the photograph had when the impressions were taken.

- Havin thus described the method, the apparatus orming the object ofthe present invention serves to carryout mechanically and in an easy andrapid manner the operation above described, and also to allow of thesub- 59 sequentv graphical tracing-on paper of'the which another smalltruck 8 controlled by map of the tract of land which in this way remainsdefinite.

in the space.

(2) The delivery group which includes: 60 (a) The appliances tofix inthe space the points having known co-ordinates. 1 (b) The appliances forthe graphic tracing of the image of the land tract on the drawingpaper.; J In the accompanying drawings, which serve to illustrate apractical embodiment of the photogrammetric apparatus according to thepresent invention: i V

Fig. 1 is'a side-elevation of the delivery 7 group'mounted onits'support; 3 j

Fig. 2 is a plan viewof the device shown in g p v p Figs. 3 and t arerespectively a side elevation and plan view'of the projector group Fig.5 is a vertical cross-section through The same reference numerals areused in the various figures to indicate the correspond, ing parts. V

The projection group issupported on two columns 1 which are verticallydisposed on a base plate. 7

. On these two columns, two small trucks 3 are made to slide by means ofguides, independent of each other, and symmetrically arranged, each ofthem controlled by the hand wheels 4, 5 which-act by means of gears onthe two toothed racks 6. i V

Each of the said small trucks carries a system composed'of a transversalslide? on the handwheel 9 is made to run.

. On the small truck 8' another-slide 10 is mounted or orthogonally tothe first, on which by means of the handwheel 11 the small truck 12canbe made to slide. e i

This latter acts as-the immediate support 100.

' proper,

of the projection device which consists of a main body which includesthe optical system formed of the objective, the focal planes 13, 14 thecondenser 15 and the light source 16.

This central body is supported on its front part by a ring fitted withtwo lateral projections 17 which rest on the vertical fork 18 providedon the front part of the truck 12 thus forming a universal joint thecentre of which coincides with the optical centre of the objective, ormore precisely with the emerging point of the said joint. 1

The control body can-rotate on itself in its forward part, moving in thering carrying the projections, and in its back portion rests on a pivot62 which is inserted in a hole provided coaxially on the prolongation ofthe principal axis of the optical system.

As more clearly shown in Figs. 6 and 7, the pivot 62 terminates in afemale screw 63 held by the screw 19. On the female screw is arranged ahand wheel 20 provided with a screw which acts on the spur gear 21 fixedon the central body.

Lastly, the screw is held by a small fork 23 which in its turn issupported by a pivot placed in a normal direction to the rotating planeof the screw 19 and in the position of the drawing on the prolongationof the optical axis.

The hand wheel 24 serves to rotate the spur gear 25 and consequentlyalso the small fork 23 and the screw provided on it. The hand wheel 26connected with two conical gears serves for the rotation on its axis ofthe screw 19 which by shifting the female screw 63, causes acorresponding movement of the central body of the optical system towhich it is joined by means of the pivot 62.

With the contrivance above described the movements which canbe made ineach optical system are the following:

(a) Movements in the direction of three orthogonal axes (co-ordinates)by using the three hand wheels 4, 9 and 11.

(b) A rotating movement of the system round its own optical axis bymeans of the hand wheel 20.

(c) A movement of inclination of the optical axis with pivot on thesecond nodal point of the objective by means of the hand wheel 26. V (d)A rotating movement round an axis resulting from a plane including thisaxis and the optical axis in any of its inclinations'that it may assume.This movement is caused by the hand wheel 24 which causes the rotationof the screw 19 in a plane which is normal to a line running from theoptical centre to the support of the small fork 23. The screw 19 isconsequently always in the plane of inclination desired; the other, ormechanical axis which corresponds to 0 inclination of the optical axis,is vertical when dealing with aerial photographs.

The object of the arrangement above described is to obtain by means ofrapid and easy movements the coincidence of points on the ground whichhave co-ordinates already known, and which are materially reproduced inthe delivery group with those corresponding inthe projection group.

In fact this series of six movements can be subdivided into two separateand distinct groups as follows: 7

(a) Movements designed to obtain the superposition without deforming thefigure.

(b) Movements designed to obtain a given deformation.

The first group of movements includes the two hand wheels 9 and 4 aswell as the hand wheel 24; the first two because they shift theapparatus in the precise direction of two coordinates, the third becausewithout altering its inclination, it allows of the rotation of thefigure round the axis of inclination (zero) which, in other words, isthe vertical line running from the centre of the objective glass to theplane of the horizon.

The second group includes the following contrivances the hand wheel 11by which the distance, and consequently the size of the image may bevaried. The'hand wheel 20 which, by rotating the figure round theoptical axis deforms the said figure on the horizontal plane when theoptical axis does not coincide with thecentral vertical axis of thesystem.

The delivery arrangement consists of the two following parts:

(a) the group of the movable screens,

(1)) the system for the drawing and for the graphic reproduction of thereconstructed image.

The group of the movable screens is supported by the two columns 30disposed vertically on the two sides of the system.

Each column carries four movable supports, one for each screen, whichare'conse quently eight in all.

Each support is constructed with a tube 31 which can slide horizontallyin a direction perpendicular to a plane of general reference of thesystem which corresponds to the horizon of the reconstruction of theground.

Each tube 31 carries (Fig. 2) at its'front end and at right angle,another tube 32 which terminates with a ball joint 33 which allowsanother tube 34 to rotate in a direction parallel to the plane abovesaid, and to slide along its own axis. At the end of this tube 34 asmall bearing 35 is provided which allows of two shifting movements andof one rotating movement so asto allow a small screen 36 (consisting ofan emery glass with central hair lines) to assume with small micrometricmovements a given position in the space to which it has prevlously beenbrought apsaid supports.

Thef'system for the graphic tracing iin eludes a principal table '37resting with an adjusted slidingplane on the wheels 38 running-on theadjustable supports 39.'I .This

'planeof the reconstruction.

ta'blecan' beinoved on'the said wheels by means of ahand wheel 40controlling a screw.

elwhiclracts onafemale screw fixed to the v y ,f grooved shaft 57 arealso disposed transvers vally and in 'a' p arallel'directionto the truckv V fel-so that the end of each shaft'is project- I ingion' the plane ofthe'supports.

A special arrangementfof".oounte'rpoised" side wheels 43- acting ion thecorresponding two rectified planes allows 0f the shifting of the; tablein the desired direction, the 'oon struction of which isnorma lto'thehorizontal On the table'a-bove cl'escrib edftwo pairs ofguiderails arefitted in a: trans-verseidireo -tioli to ts' movement;twoof'these'guldes 44 areoutside'andon' these the truck45rests andslides; the otherftwo" guides 46 'areinternal,

- and onthese the truck 4-? rests and slides.

f The'two'said trucks havea rectified parali' "salicl reconstruction ona sheet of ,paper laid Fi i lo the principal table. t I e The verticalmovement of the screenfrajme ally controlled bya screw 54(Fig, :1arranged Vertically;

'le'l movement on the borders of one of two 'gu'ides,-so as to -maintainthem parallel tothe horizontal plane ofthe-reconstruction;' The truck'45 carries on its front part vertical rod-48 onwhich slides ascreenframe :49consistihg'ofan emery; glass Wlth' centre hair lines, use'd asooll'imatorffl i The truck 4s? carries horizontally adapted to carry a"pen cillwhich 'traces' the on the drawing board 51" (Fig g 'Thetransverse movement'of the truck in the direction'of the principal: g'uide is con Y trolled by ascrew 52 supported at the ends on the twofplates53 which also are provided on v This screw s connected; means oftwo.lconical" gears to a grooved shaft 55 disposed in a transverse directionsothat when shiftingth'e truck 4501i acount of its'transverse movement,the set of conical; gears is shifted:

along groovedshaft; consequentlyby acting simultaneously on the screw ofthe-truck and on the grooved shaft, itis possible tomov e in: any of thetwo directions and with any Velocity the truck 45 ina transversedirection5 v y tions ofthe same. g t e 7 I The first result is obtainedby shifting the and the screen 49 in a vertical direction In the mannerabove described the cross hair lines on the screen can be made to assumeany desired position in the plane-ap pertaining tothem and which is theone 'coinciding with the horizon" of the reconstructed 1 ground bysimply acting simultaneously on p 1 "of level. Afterwardsythe smallscreens, one

I the two hand wheels.

By shifting back or forwardthe of the truck 47 indifferently.

ing-results: I

1 (a) To. obtain'thereconstruction of; vthe "landtrachby utilizing thecoordinatesoffis known points, with i the same index with er horizon"planes by ai movement of transla- The truck meansof a} mechanicalshifted horizontally in a direction normal to the movement of the truck.t

The: vs'crewj56 of, the truck 47' and the 1 On'thetw'obase planes, 'asuitable system i t t s "to the. gear of the. screw cutting'headsf ofofintcrchangeable .gear is provided, similar lathes 'and which allowstheY-jconneotion in couples of the saidshafts, viz ;any one of theshafts of thetruck 45witheach of the Shafts Lastly,the-screw 41 whichcarries the {whole table 37 with a transverse motion, is connected bymeans of comcal gears'to the longitudinalshaft 58 lyingon the sameplane.

' 'as theshafts'inentionedaboye; so that it may,*. by means-of "suitablegear, be connectedwith anyone of-the shafts of the truok47.

. "On the Y front of the principal; table 37 (Fig. the brackets 59 areprovidedwhich carry a crossmeniber 60 on which are sup-" e a rod'50fitted normally to 'tlie horizontal plane ofqthe V Vreconstru c'tionyonwhich slides a truck 51 ported the control hand wheels, 7' y 1 These 1for theobse-rvationof the screen.

as to read the decimals of a millimetre, I Thei objec t'of the'arran'gementabove described isto enable onefto' obtain the followhandwheels'control'the shafts e1; of thetru'clr lii and the translatlonmovemeiit of the table 3'? and. are, arranged 1n such a position Eachofl the two movements oflthe I Y "trucks'and of'thetable-is graduated'sowhich the deliveryand the fd rawing are lmadegif v i a I (bywTO' tracethis reconstruction. onflthe dra-wlngwlth any desired ratlo ofreduction? (0) ;By suitably connecting the shafts it is 'possible todraw the lines of equal altitude of theground as well as any. verticalsecthe table itcan be made to assume the posi tions corresponding to thesingle differences I at a time, are brought to the position of the V theposition of the individual trigonometric V tne small screens arewithdrawn and the depoints. V

Liastl' when the coincidence oi the same a points on me two positionshasbeen obtalned with the single screens, and having thus ob tained thercai reconstruction of the land tract photographed within the givenspace,

livery or drawing stage is commenced by moving the hairlines of theprincipal screen 49 along trigonometric points in the po-' sition ofcoincidence of the two images, as

tualgraphic drawing is obtained with a rewell as any other point on theland tract.

"The movements ofthe screen b means of 1 toe described connections ofthe shafts as duction of scale.

Lastly as the various connections of tilt:

' control shafts of two trucks and of the table i Y other can be made atwill, the following results can be oliitained: l

(a) ny coupling thetwo shafts 52, 55 of the truck 4:5 with the other two56, 57 of the truck 47 either in one way or another, the inversion ofthe two plane coordinates is obtained, viz; the coordinates of the ronstruction with the drawing. z r

(5) i coupling the shaft ail which serves to move the table 57 with oneof the shafts oi Lhetruclr carrying the pencil, and the with one of theshafts of the truck carrying the screen frame, (theprofile or section ofthe ground inthe direction of any one of the co-o-rdinates is obtained.r

I claim:

l. Photogrammetric apparatus forfltracingthe drawing'corresponding to'aland tract represented by two photographs, comprising in combination twoprojecting apparatus having their axes disposed in the same relativedirection as the axes of the optical-system usedfor obtaining theimpression of the image, means for supporting and controlling saidoptical systems consisting of two vertical columns, two guides fixed oneach of for drawing the map corresponding to the rying four of the saidsmall screens by means of articulated rods, controlled with microthegraphic co-ordinates of 7 'screen shdably earned on s'aid'rod, a secsaidcolumns, two trucks symmetrically disposed to run independently on saidguides, handwheels for controlling said trucks, a 1 transverse slidecarried on each of said trucks, a truck slidable on each of saidtransverse slides, a slide mounted orthogonally to each of 7 saidtransverse slides and carried by each of said trucks running onsaid'transverse slides, a projection device mounted on each of said twoorthogonal slides, enabling the universal and independent movement-ofeach of the two systems of'projection in the direction of the threeorthogonal co-ordinate axes in space, a rotating movement about theoptical aXis,-'a,movement of inclination of the optical axis and arotating movement about. an axis determined by the plane comprising thesaid axis and the optical axis in any inclination it may assume; adrawing system two photographs and comprising a number of small screens,each fitted with translucent glass and hair lines, two vertical columns,disposed at the sides of the system, each oar-1 metrical devices, adrawing apparatus compris ng a movably mounted main drawing board, twotrucks disposed to move in the transverse direction to the movement ofsaid drawmg board, a verticalrod carried in the fore part on one of saidtrucks, aprincipal ond rod mounted on the other truck, disposed normallyto the plane of the horizon of the reconstruction, and a truck adaptedto carry a pencil, said'last mentioned truck being slidably mounted onsaid second rod.

2. A photogrammetric apparatus according to claim 1, in whichthe smallor second- 'ary screens are provided to successively assume the positionof the principal screen connected to the drawing system for the tracingof'the map, and fastening devices permitting said screens to be fixed inspa'cein the relative position of the known points on the ground, thecoordinates of which are set by means of said principal screen.

In testimony whereof I have afiixed

